Burner heads



C. A. H. WILLIAMS BURNER HEADS Oct. 8, 1957 Filed Sept. '7, 1955 Av VE/V TM CAWIELES raze A isa E67 Mum-1.1

a free NEY United States Patent BURNER HEADS Charles Avalon Hinvest Williams, Grain, England, as-

signor to The British Petroleum Company Limited, London, England, a British joint-stock corporation Application September 7, 1955, Serial No. 532,976

Claims priority, application Great Britain September 14, 1954 4 Claims. (Cl. 98-58) This invention relates to an improved wind deflector for use on flare stacks and to flare stack burner heads comprising said Wind deflectors.

In the refining of mineral oils, particularly petroleum oils, there is usually produced and/or separated from the oils, gases comprising hydrocarbons having 1-3 carbon atoms/molecule. While it is possible to utilise these gases or components of these gases either in hydrocarbon conversion reactions for example polymerisation, or as a works fuel, there will usually be a fluctuating surplus make, which cannot be absorbed in this manner, and it is customary to burn off this surplus gas at the head of a flare stack.

In the operation of a flare stack it has been found that considerable damage may be occasioned under conditions of high wind by the downward deflection of the flare on the leeward side of the burner head. Under these conditions the heat generated alongside the burner head may cause the head to buckle with damage to the lining of insulating material attached thereto. Furthermore, damage may be caused to the ancillary equipment, that is, the pilot tube and electrical firing gear, attached to the flare stack, by which the flare is ignited.

According to the present invention there is provided a flare stack burner unit comprising a burner head and, attached thereto, a wind deflector comprising at least one Wind deflector member by means of which, in operation under windy atmospheric conditions, air is caused to pass to the leeward sideof the flare stack, by deflection and/ or by the creation of turbulence, in such manner as to prevent the formation, in the lee of said stack, of a low pressure zone, as hereinafter defined. The term low pressure zone is used herein with reference to a zone, to the leeward side of a flare stack, wherein the air pressure is sufliciently below prevailing atmospheric pressure to cause downward deflection to said zone of a flare burning at said flare stack.

Preferably the flare stack burner unit comprises a plurality of vertical elongated members set about the burner head, each member being spaced from the burner head and from adjacent members in such manner as to deflect air to the leeward side of the stack under differing wind directions. Preferably the vertical elongated members consist of vertical slats. It will be apparent that it is necessary for the relationship of the width of the slats to the interval between the slats to be such as to perm-it sufficient air to flow between the slats while, at the same time, providing sufficient deflection of the wind to prevent the formation of a low pressure zone. Furthermore, it is necessary to space the slats at a suflicient distance from the burner head to prevent the formation of a low pressure zone on the side of said slats remote from the burner head, while at the same time providing a suflicient degree of wind deflection to prevent formation of a low pressure zone between the slats and the burner head. In practice it has been found that the above conditions are easily fulfilled and, if desired, may be deter- Patented'Oct. 8-, 1 957 2 mined without difliculty with the aid of small scale models. I

Preferably the vertical elongated members havetheir upper ends terminating at, or slightly below the top of the burner head. The members should be of suificient length to prevent the flare striking down to a low pressure zone lower down the burner head, under normal atmospheric conditions. In general, the length of the members willl be not less than 3.5 times the distance between the slats measured diametrically across the burner head, The members and burner head are preferably made of steel, mild steel being found to be quite suitable. Other materials such as stainless steel or InconeP can be used if desired.

Conveniently the burner head will consist of a cylindrical pipe of smaller diameter than the main flare pipe being coaxial therewith and connected thereto by a reducer section. The vertical members may then be attached to the main flare pipe at their lower extremities and secured at a higher level, through the means of spacer members, to the burner head pipe of smaller diameter.

Preferably the vertical members are vertical slats, each having a tapered upper extremity, and being curved towards the burner head pipe, whereby an upward draught is created on the leeward side of the burner head.

The invention is illustrated with reference to the drawing which is a vertical view of the new burner head.

For clarity, two vertical slats to the left of the centre line are omitted from the drawing.

With reference to said drawing, the uppermost flare pipe, section 1 is welded to a frusto-conical section 2 to which is welded the burner head pipe 3. Fifteen metal slats 4 are spaced uniformly about the burner head and are secured at the lower extremities to the pipe section 1 by bolts 5. Clamp rings 6 and 7 are secured to the burner head pipe 3, the slats being bolted thereto through distance pieces 8.

The upper extremity 9 of each of the slats 'is tapered and the tapered sections are curved towards the burner head pipe 3.

The pilot tube 10 is secured by clamps 11 and 12.

The invention is further illustrated but in no way limited with reference to the following description of typical dimensions.

Flare pipe section 1: Outside diameter, 2 ft. Burner head pipe 3: Outside diameter, 1 ft. 1 in. Slats 4:

Length, 7 ft. 3 ins. Width: 3 ins. Width (top of taper), 2 ins. Thickness, 0.375 in. Distance of slats 4 off burner head pipe at curved upper extremity, 3 ins. Distance of slats 4 off burner head pipe at their midportions, 5 /2 ins.

I claim:

1. A flare stack burner unit comprising a cylindrical burner head and, attached thereto, a wind deflector consisting of a plurality of vertical slats having their width lying on a circle concentric with the burner head, said slats being set about the burner head, each slat being spaced from adjacent slats and from the burner head, and the length of each slat being not less than 3.5 times the distance between the slats, measured diametrically across the burner head, and the upper extremity of each slat being curved towards the burner head and being free of contact and connection with said burner head.

2. A flare stack burner unit as specified in claim 1 in which the upper extremity of each of the slats lies at or below the level of the top of the burner head.

3. A flare stack burner unit as specified in claim 1 in I which the burner head consists of a cylindrical pipe of lesser diameter than the flare stack pipe and a reducer sectionby which said-cylindrical pipe is attachable. to said stack pipe. r

. 4 A flare stack burner unit as. specified in claim 1 in References Cited in the file of this patent UNITED STATES PATENTS Eby Aug. 10, 1943 

